Aluminum in Spray Mode Problem

[ampdog]

Ok Guy's, I'm welding 1/8" Aluminum. I'm confident of my settings cause I have sucessfully put down some welders that I am really proud of.

Problem is; I'll be traveling along at a consistent speed watching my filler metal drop into the joint. Drip, drip, drip, drip, making a nice puddle/bead then its like a drop gets stuck to the tip and a pool of filler metal grows quickly and falls / splashes on the material and bench. Basically the wire keeps feeding, but stops dripping, until the drip is huge.

I have tried it several times observing different things, cleaning the tip, making sure I don't change the angle of the gun, or speed. But, I don't seem to be able to get more than 3 1/2 inches or so of good bead before the problem starts to occur again.

Anyone, have this problem before? Any advice or tips for me?

Thanks in advance!

[Scott V]

Ampdog,welcome to the wonderful world of wirefeed welding of aluminum. It might help if you give some info on the type of joint you are welding.Sometimes when welding a fillet joint the puddle can get ahead of the cleaning with a cv power supply.When using a cc type power it bites in or wets out a little better in that type joint,although 1/8 is a little thin for cc power.Unless you are pulsing it.What type off machine are you using?Even with the best stuff there is for aluminum welding,seems like it's always something.I kind of think the guy that invented tig welding must of started out using wirefeed for aluminum welding,and thought there must be a better way.

[ampdog]

Thanks for the reply Scott V!

I am using 4043 (.030) wire. I have a Lincoln SP-135 Plus. I couldn't find a term for the joint, I know its not proper structurally, but its a light weight application and its where I need to weld. See the attached sketch.

I was thinking on my way to work this morning that maybe when laying the long bead the wire gets too hot ( I'm moving pretty slow but getting a nice weld) and is starting to melt before it leaves the tip, causing my problem. Thinking maybe I should use 5356 wire........

Does that sound possible?

[rangerod]

Aluminum Welding

ampdog

Did you buy the aluminum welding kit for this unit from Lincoln? With this unit does anyone know if it would make any difference if .035" wire was used instead of .030"? I have one of these units & wanted to know if it was worth spending the $60 for the aluminum welding kit?

[Scott V]

Thats probally whats happening,so space it out and grind a little if needed.If you can get away with 4043 with your setup more power to you,It usually looks better than 5356 with less splatter.

[Mike Sherman]

There are only five types of joints: Lap, Tee, Corner, Butt, Edge. Yours is a corner joint. If you are getting drops of filler metal larger than the diameter of the wire itself, it is a good indication you are in globular transfer mode, not spray. Your problem seems to stem from the fact that you are pushing aluminum wire through a liner without a push pull system or a spool gun. Often this will work fine, but as you progress along the weld you move the gun which in turn moves the liner. It only takes a very small amount of friction on the soft aluminum wire to bind it up and in effect change your wire speed. When you change your wire speed you will get either burn back or stubbing out. You have described burn back while in the globular transfer mode in your post. This is why if you have alot of aluminum to weld, you will need a push pull or a spool gun. If you are not careful this will also cause a pretty good birdsnest in your liner.

[ampdog]

Re: Aluminum Welding

Originally posted by rangerod
ampdog

Did you buy the aluminum welding kit for this unit from Lincoln? With this unit does anyone know if it would make any difference if .035" wire was used instead of .030"? I have one of these units & wanted to know if it was worth spending the $60 for the aluminum welding kit?

Nah, I still have the original liner. I have been thinking along the same lines as you. But, when I went to switch out wire last night I did see Aluminum dust / shavings, which could be part of what cause these wierd problems, so I think I am go to get the Aluminum kit.

I changed wire from 4043 (.030) to 5356 (.035), which is harder and thicker. 5356 (.035) is stiffer that the .030 steel wire I was using. I don't think there is a chance in **** of a birds nest with that wire. But, I'm still going to get the kit cause I don't want the shavings to clog the liner.

[ampdog]

Thanks for the reply Mike! You got me pointed in a good direction!

Here is what I did. The only reason I could come up with for going into globular transfer mode is cause my wire feed speed was becoming too slow during the weld. Maybe due to the liner I have, hopefully the Licoln Aluminum kit will do me, but I can definately see the need for spool guns very clearly now. So, I tried to increase wire speed, but then I got splatter. I tried to play with it (fine tune) but it was either glob or splatter. So, I said ok let me switch wire to 5356 (.035), maybe the stiffer wire will help keep my wire feed speed consistent (and keep me spray mode).

At the same time I switched the wire I had run out of corner joint on the practice metal I was using. So, I flipped it over figuring the type of joint wasn't the issue as long as is didn't glob. So, now its like I'm welding in a fillet or T joint. A little splatter, but pretty nice. I turn down the power a little, slow down the speed a little and get a nice weld in the reverse side joint. So, I think I have it licked. I put together 2 more pieces of practice metal and start to practice the corner joint again with the new setup, I don't touch the settings at all. And an inch and a half down the bead it starts globing again.

WHY??? It didn't glob in the T.

Anyway, I sit down and start thinking. When the glob starts its almost like the tip of the drip gets hung on the tip of the gun. If I had more stick out the drip would start too far away from the tip for this to occur. So, I unscrewed the nozzle of the gun as far as I could without it falling off (like a recessed tip) and tried it again. It seemed to work really well. With my luck it will screw up as soon as I try to weld my good metal.

[Sberry]

Just a guess, but I think you might need to increase travel speed as you go. With that type of joint the base metal is going to really heat up in a hurry after a bit. When you had the fillet going you already had welded one side and had a way much better heat sink than on those edges.

[rangerod]

Aluminum Welding Kit

ampdog

Could you post your results with the aluminum kit when & if you get it Thanks

[bjdenommee]

Hi Guys
I found the best way to mig weld aluminum is to let someone else do it, birds nests with tip and liner problems are a fact of life in that business when you use a mig machine in the push only mode, I do not think that I have ever been more upset at my equiptment for letting me down.

Then I got first a spool gun and up graded to a push pull gun they do make life a lot more fun and a lot less demand on the machines.

Good Luck
Bernie

[morpheus]

what kind of gas and brand/type of wire were you using aaron ?

- jack

[morpheus]

cool. how well did it work ? come on post some pics

- jack

[ampdog]

Ok, guys I finally got back to this project after purchasing some hardware.

Again, I have a Lincoln SP-135 Plus and I'm welding 1/8 aluminum. I purchased the aluminum kit, but haven't installed it yet. One upgrade at a time so I can see where the performance really changes. I'm using 5356 (.035) wire to counter act the birds nesting and I also take care to keep my hose and gun as straight as possible. I have not had a birds nest yet, although I think I was seeing inconsistent wire speed with the 4043 (.030) wire. I installed a longer nozzle for the recessed tip effect (Lincoln part# M16684-1). I got a tapered tip (Lincoln part# S20278-3), but I didn't use it. I took an old .350 tip that I had and used my grider to taper it real quick, because I'm cheap . My voltage is set at "I and a half" (Lincoln has letters on the dial) and wire speed is about 6.8.

This setup has allowed me to put down several consistent beads in 2 to 3 ft passes!! I have a nice long stick out (thanks the the new nozzle) and I can see every drop in my puddle. No globing cause the tapered tip doesn't have the surface area for the molten aluminum to hang on. It is working great! Should be even better when I install the aluminum kit.

[rangerod]

Aluminum Welding

ampdog

Thanks for the reply Do you have any pics of your welds? Looks like you have this process licked. I can't wait to see how it does WITH the aluminum kit. Good job!!!